An irregular pattern input device includes an optical fiber bundle in which an entrance surface and an exit surface are respectively formed at both ends thereof. Lighting means emits irradiation light so as to provide a light pattern according to a convex portion of a subject in contact with the entrance...http://www.google.com.hk/patents/US5426296?utm_source=gb-gplus-share專利 US5426296 - Irregular pattern input device comprising an optical fiber bundle
